Write Null in Database if the TextBoxes are Empty

Question

All I want to do is to insert Null with the database when the textbox is empty.

 --ACCOUNT

 AS
 BEGIN
-- SET NOCOUNT ON added to prevent extra result sets from
-- interfering with SELECT statements.
SET NOCOUNT ON;
SET IDENTITY_INSERT account ON


  INSERT INTO dbo.account
      ( 
        AccntID                   ,
        managedby                 ,
        AccountHolder             ,
        Description               ,
        AccountType               ,
        ContactPerson             ,
        ContactNumber             ,
        EmailAddress              ,
        Address                   ,
        ClientTYpe                ,
        SchemeType                ,
        SalesManager              ,
        DateCreated               ,
        Login                     ,
        Password                  ,
        Balance                   ,
        FilterOption              ,
        Enable22                  ,
        AllowExtendedConfig                  
      ) 
-- Insert statements for procedure here

 VALUES (@AccntID, @managedby, @AccountHolder, @Description, @AccountType, @ContactPerson, @ContactNumber, @EmailAddress, @Address, @ClientType, @SchemeType, @SalesManager, @DateCreated, @Login, @Password, @Balance, @FilterOption, @Enable22, @AllowExtendedConfig)
SET IDENTITY_INSERT account OFF



END

What is the best way to add NULL values to the database when my textboxes are empty

Answer 1

Set up helper functions such as:

Public Function DbNullOrStringValue(ByVal value As String) As Object
    If String.IsNullOrEmpty(value) Then
        Return DBNull.Value
    Else
        Return value
    End If
End Function

And so the first code block would be simplified by calling it thus:

Cmd.Parameters.AddWithValue("@AccntID", DbNullOrStringValue(TextBox1.Text)) 
Cmd.Parameters.AddWithValue("@managedby", DbNullOrStringValue(TextBox2.Text)) 
Cmd.Parameters.AddWithValue("@AccountHolder", DbNullOrStringValue(TextBox3.Text)) 
Cmd.Parameters.AddWithValue("@Description", DbNullOrStringValue(TextBox4.Text)) 
Cmd.Parameters.AddWithValue("@AccountType", DbNullOrStringValue(TextBox5.Text))

Cmd is your SqlCommanad object

Answer 2

Consider something lighter than a new method :

    Cmd.Parameters.AddWithValue("@AccntID", IIF(String.IsNullOrEmpty(TextBox1.Text),  DBNull.Value, TextBox1.Text)) 

But for the rest, use a SqlDataAdapter as suggested before.

Answer 3

The best way will be to inherited text box and add additional functionality to it

Public Class MyText
    Inherits TextBox

    'Either change default text property (but this will bug you while comparing text property)
    Public Overrides Property Text() As String
        Get
            Return MyBase.Text
        End Get
        Set(ByVal value As String)
            MyBase.Text = value
        End Set
    End Property

    'Best way will be to write new property to use in sql query
    Public ReadOnly Property TextSQL() As String
        Get
            If Me.Text = String.Empty Then
                Return "NULL"
            Else
                Return Me.Text
                'Return "'" & Me.Text & "'" 'or this
            End If
        End Get
    End Property
End Class

now use this text box in your application

cmd.Parameters.AddWithValue("@accountholder", txt_accHolder.TextSQL)

Answer 4

In the stored procedure you can use following:

Assumption: parameter name is @TextData

 NULLIF(LTRIM(RTRIM(@TextData)),'')

It will return NULL if @TextData = ''.